In general, an endotracheal intubation refers to an airway maintenance method which is essentially performed for a patient who suffers from respiratory failure or airway obstruction or a patient who requires aid to influence breathing such as a patient under anesthesia.
An endotracheal tube is used for such an endotracheal intubation. The endotracheal tube is intubated into the inside of the trachea mainly through the mouth (or nose) and then through the oral cavity, the pharynx, the larynx, and the glottis. Thus, the endotracheal tube is fabricated in a shape somewhat curved forwardly in consideration of the human body's structure through which the endotracheal tube passes in the process of intubation.
When performing an existing endotracheal intubation, the endotracheal tube should be bent further as compared with the curvature of the endotracheal tube formed at the time of fabricating the endotracheal tube in order to facilitate the intubation into the trachea. Thus, the intubation is typically performed in a state where the endotracheal tube is bent further by inserting a relatively rigid iron core into the endotracheal tube.
Individual patients who need endotracheal intubation have different anatomical curvature of the airway where the endotracheal tube passes through. Therefore, there is, not infrequently, a need to change the curvature angle of endotracheal tube while endotracheal intubation is being performed. However, the existing endotracheal tube is hardly bent further or unbent in the process of performing the intubation when the endotracheal tube is used in the state where the iron core is inserted into the endotracheal tube. This is because it is impossible to bend the iron core in the state where the endotracheal tube is intubated into the trachea.
Accordingly, unless the curvature maintained by the iron core is suitable for a patient, it is required to pull out the endotracheal tube again and adjust the curvature of the endotracheal tube. However, this may delay the intubation and put the patient in danger. Further, when the iron core is exposed to the outside of the endotracheal tube, the iron core may pierce the trachea, thereby causing serious damage or bleeding.
In addition, after the endotracheal intubation is completed, the iron core should be removed. In the process of removing the iron core, the endotracheal tube may be pulled out from the trachea.